Lock.



G. N. STRICKLAN.

LOCK.

APPLICATION FILED APR. 20. I915.

Patented Sept. 21, 1915.

vwemtoz Sink/Han COLUMBIA FLANOGRAPH co.,wAsHlNOTON. D. c.

GEORGE 1v. STRICKLAN, or SAVANNAH, GEORGIA.

LOCK.

T all whom it may concern:

Be it known that I, Gnonon N. S'rnionLAN, a citizen of the United States, residing at Savannah, in the county of Chatham and State of Georgia, have invented new and useful Improvements in Locks, of which the following is aspeciiication.

This invention relates to locks and the principal object of the invention is to pro vide a lock having means for securing the ordinary latching bolt in projected position so asto obviate the necessity of employing an additional locking bolt thereby cheapening the construction of the lock.

Further objects of the invention will appear as the followingspecifie description is read in connection with the accompanying drawings which form a part of this application and in which Figure 1 is a side elevation of the lock with its side removed, Fig. 2 is a rear end elevation with the end plate removed, Fig.

3 is a detail side elevation of the opposite side of the lock with parts broken away, Fig. i is a perspective view of the latching dog, and Fig. 5 is a similar view of the looking plate.

Referring more particularly to the drawings 1 represents a suitable lock easing here shown in the form of a mortise lock casing having a front plate 2 through which is projected the ordinary latching bolt 3 the latter having a customary yoke end l whose upstanding terminals are engaged by the lateral arms 5 on the knob cylinder 6. Slidably mounted crosswise of the cylinder and arranged between the end plate 7 and the yoke end lof the latching bar is a locking plate 8 having a longitudinal slot 9 to receive the actuating spring 9 which has one end engaged with the inner wall of the slot and its opposite end engaged with a pivot pin 10 the purpose of which will be hereinafter described. The locking plate is also provided with a longitudinal slot 11 in which is located a guiding pin 12 projected laterally from the side plate of the casing. Immediately adjacent the slot 11 the plate is provided with a forwardly projecting cam extension 13 and at the opposite end with a parallel extension ll both of which are adapted to lie in the path of the legs of the yoke end when the locking plate is thrown into operative position. 7

15 having a lateralcam extension 16. The

Pivoted upon the stud 10 is a locking dog.

7 Specification of Letters Patent. Patented Sept, 21, 1915 Application filed A ril 20, 1815. Serial No. 22,692. 2

dog is also provided with a springlS located thereon with its end iirengagement with the end 7 of the casing so that the free end of the locking dog 15 normally has a tendency to move toward'the front of the lock. Project ing at right angles to and carried by the free end of the locking dog is a locking pin 19 arranged within the slot 20 formed in the locking plate, which slot is provided with a lateral off-set 21 also adapted to re-, ceive the pin as will be hereinafter described.

When the key 22 is inserted in the lock and turned in the proper direction, its tang will engage the cam' extension 13 of the locking plate and move the plate across the casing so as to position the extensions 13 and let in the path of the legs of the yoke head of the latching bolt. When moved to the full extent the locking dog will be shifted by the spring 18 so as to. cause the pin 19 to engage in the extension 21 of the slot 20, thereby securing the locking plate in operative position and preventing the retraction of the latching bolt. In this position the cam face of the extension 16 will be projected into the path of the key tang so that when the key is rotated in the opposite direction the free end of the locking dog will be moved rearwardly taking the pin 19 out of the extension slot 21 and permitting the spring 9 to restore the locking plate to normal position. The latching bolt is of course, normally projected by a spring 3'" and is retracted as is usual by the actuation of the knob and its associated knob cylinder.

\Vhat is claimed is 1. In a lock, a casing, a spring projected latching bolt slidably mounted therein and having a yoke end straddling the knob eyl-o inder, a spring actuated and key operated locking plate having parallel extensions adapted to be arranged in the path of both of the legs of the yoke and means for securing said locking plate in operative locking position, said means being actuated by a key to release the locking plate.

2. In a lock, a casing, a spring projected latching bolt slidably mounted therein, a knob cylinder having lateral arms, a yoke head on said latching bolt straddling the knob cylinder, a slidably'mounted locking plate having lateral extensions adapted to be arranged in the path of the legs of the yoke head, said locking plate being provided with an L-shaped slot and one of said extensions having a cam face adapted to be en- V the locking plate in one direction for carrying :1 pin fitted Within the L-shaped slot,

gaged by a key tang, 2L spring for moving piz te in operative latching bolt locking po- 10 sition.

In testimony whereof I aflix my signature in presence of two Witnesses.

\Vitnesses H. G. DEBEES,

C. E. ALEXANDER.

ing the extension out of the path of the legs of the yoke head, a pivoted locking dog hevsaid dog having a key-operated extension and a spring for throwing the pin of the locking dog into engagement With the short leg of the L-shaped slot to secure the locking Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

' Washington, D. 0. 

